Investigation on IGBT High-Frequency Plasma Extraction Transient Time Oscillation

High-frequency voltage oscillations occasionally appear between insulated gate bipolar transistor's (IGBTpsilas) collector and emitter terminals during turn-off operation. Based on the plasma extraction transit-time theory, the turn-off oscillations were investigated experimentally and analytically using real-sized high-voltage IGBT modules. Generating mechanism of the turn-off oscillations was clarified by 2D device simulation. In addition, a practical method for preventing the turn-off oscillations will be proposed in the paper.